Norman M Abramson, 56212 Sunnyridge Cir, Minneapolis, MN 55422

6625204, Sep 23, 2003

Apr 23, 1999

09/296589

Norman Abramson - San Francisco CA
Eric Copeland - Los Altos CA

Aloha Networks, Inc. - San Francisco CA

H04B 169

375152, 375342

In simultaneous reception of overlapping signals sharing a single spreading sequence, packet start times are found by separately demodulating, low pass filtering and despreading in-phase and quadrature components. Despread in-phase and quadrature signals are provided to sychronization filters connected in parallel and arranged in two identical pairs. Outputs from filters in different pairs are added, and the sums are squared. The squared signals are added. An exceeded threshold of the output from the last adder delineates a packet start. Knowing packet start times facilitates separating the overlapping inbound signals.

6046991, Apr 4, 2000

Apr 9, 1997

8/835420

Norman Abramson - San Francisco CA

Aloha Networks, Inc. - San Francisco CA

H04B 7185

370318

Broadcasting of data packets from a hub station to many remote terminals in a two-way data network uses a spread spectrum time division multiplexed (TDM) channel. A channel in the other direction is a multiple access channel. To provide substantially equal energy per bit of the received signal at each of the remote terminals for maintaining reliability per bit at all terminals, the spreading factor of number of chips per bit is increased according to the distance of the remote terminal from the hub or the strength of the signal from the hub received by the remote terminal. The spreading factor or number of chips per bit may be changed according to the strength of the signal received by the hub from the remote terminal. Terminals positioned around the hub transmitter are located in regions arbitrarily determined by signal strengths, terrain, weather conditions or range. Fixed receivers in the closest region receive signals with the lowest spreading factor or number of chips per bit, and terminals in the furthest region or the region most affected by signal strength reduction receive signals from the hub with the highest spreading factor or number of chips per bit.

5745485, Apr 28, 1998

Jun 19, 1996

8/665843

Norman Abramson - San Francisco CA

Aloha Networks, Inc. - San Francisco CA

H04J 1300

370342

A simplified process of signal detection in a multiple access data communications uses a small number of different spreading signals rather than a single spreading signal such as used in a Spread ALOHA multiple access network. The process selects a spreading signal which depends upon a property of the signal being transmitted rather than upon the transmitter which is transmitting the signal as in Code Division Multiple Access (CDMA). Multiple transmitters can use pilot signals and transmit the multiple data signal with the selected spreading sequences. The hub station receives the multiple data signals and detects the multiple data signals with matched filters or correlators matched to the code spreading sequences. Outputs of the matched filters or correlators can create control signals for offsetting the transmitted data signals by advancing or retarding timing of the transmitting of the multiple data signals from the multiple transmitters. The spreading signal for each transmitter may also depend upon whether the transmission is on the "in phase" channel or the "quadrature" channel, thus doubling the number of spreading codes used in the data network.

6151313, Nov 21, 2000

Jun 6, 1997

8/870298

Norman Abramson - San Francisco CA

Aloha Networks, Inc. - San Francisco CA

H04B 7216

370342

A SAMA QAM demodulator and packet detector receives SAMA transmissions from multiple transmitters. The received data packets have bits divided into chips in a first spreading sequence in the in phase branches of the transmitters, and a second spreading sequence in the quadrature branches of the transmitters. A demodulator at the hub station has a received signal splitter and an oscillator and phase shifter and multipliers for mixing the incoming signals with the oscillator output and with the phase shifted oscillator output on different branches. Low pass filters are connected to the mixers to remove the carrier signals and to leave chip signals with cosine and sine of phase offsets. The signal from each low pass filter is fed to an in phase matched filter and a quadrature matched filter, four matched filters in total, to produce despread signals from all of the active transmitters with phase relation and start offsets. The signals from the individual matched filters are passed to packet synchronization sequence detectors, which detect the start times of each of the data packets.

6252883, Jun 26, 2001

Feb 27, 1998

9/031664

Russell L. Schweickart - Tiburon CA
Norman Abramson - San Francisco CA

ALOHA Networks, Inc. - San Francisco CA

H04B 7216

370441

The invention provides both a fixed and a mobile data telecommunication service using a fixed code, direct sequence spread spectrum, connection-free data protocol as an overlay on cellular or PCS wireless services. A wide band connectionless data protocol is employed to transmit packetized digital data from a variety of home sources e. g. www inputs, e-mail, utility meter readings, security system data, to a local cellular or PCS communications hub station. From the hub station the cellular/PCS provider routes the packet data into packet networks for delivery to a variety of recipient parties designated by address within the packets themselves. The data capability is provided as a supplement to the existing communications capability of the cellular/PCS system and overlays, but does not destructively interfere with, the pre-existing voice connection oriented services.